First of all let me say that I don't have much experience with the video on my 7D at all and never even planned on using it when I bought the thing. However, one of my friends has asked me to record some videos of him playing guitar for his website. We recorded a few using the built-in mic and obviously the quality is not the greatest as far as sound goes. Last night we tried using a mixer and plugging it into the "mic" input on the 7D. It was just an acoustic guitar and a mic plugged into the mixer. Even with the levels on the mixer turned down to almost 0 there was a lot of sound distortion when playing the video. We never were able to get it sounding decent. It seemed like the mixer puts out more power than what the input on the 7D can handle. I'm pretty sure his equipment is not the problem, it is all very high quality components.
What would be the best way to record a simple video with decent sound straight into the camera? Thanks for any advice you can give. I'm still in the learning process with the still picture part of my 7D so this is waaaaay out of my league.